X-ray diffraction is a well known technique for measuring the physical properties of materials. The diffraction of X-rays gives a measure of the spacing between planes of atoms, and the measured intensities and spacings of the peaks can be used to calculate the proportions of various crystalline phases in a sample.
X-ray fluorescence is another well known technique in which X-rays are used to determine the relative amounts of atoms using their characteristic fluorescence spectra.
Such techniques can be used to measure the chemical and phase composition of samples during or after manufacturing. Increasingly, analysis is carried out during manufacture rather than simply being used to test the finished product. By doing this, it is possible to adjust the manufacturing process to improve the final result rather than simply needing to reject samples that fail quality control standards.
For example, in the cement industry, it can be desirable to test the cement during manufacture for a number of different additives, including sulphates and carbonates. Normally, such testing is carried out after manufacture, that is to say, off-line. However, the inventors are aware of one approach in which a continuous stream of cement is analysed, using equipment developed by the CSIRO of Australia and marketed by FCT- ACTech. Another approach using X-rays is X-ray computer tomography, for example as set out in “X-ray computer tomography—potential and limitation for the measurement of local solids distribution circulating fluidized beds”, Grassler and Wirth, Chemical Enginerering Journal 77 (1-2) (2000) pages 65 to 72.
However, there remains a need for improved X-ray apparatus for carrying out X-ray studies of particle or powder material.